Hepatocellular carcinoma eats medullary thyroid carcinoma, a case of tumor-in-tumor metastasis

Abstract

Metastasis to the thyroid gland is uncommon, with previous autopsy series showing incidence rates ranging from 0.5% to 10.1% [1][2][3][4][5][6][7]. Clinical reports have suggested, however, that the incidence of these metastases is increasing. The most common primary carcinoma sites in clinical reports are the kidneys, breasts, and lungs [8][9][10][11][12][13][14], although other primary carcinomas can also metastasize to the thyroid gland [15][16][17][18][19][20][21][22][23][24][25][26][27].Hepatocellular carcinoma (HCC) rarely metastasizes to the thyroid [6,23,[25][26][27]. Here, we describe a patient with an HCC metastasis to within a medullary thyroid carcinoma (MTC), that is, a tumor-in-tumor metastasis. To our knowledge, this is the first such clinically diagnosed case.Due to the relatively short survival times of patients with distant metastases, solitary thyroid tumors in patients with advanced carcinoma are not routinely evaluated. However, imaging modalities, including fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and ultrasonography (US) guided fine-needle aspiration biopsy (FNAB) of newly detected Hepatocellular carcinoma eats medullary thyroid carcinoma, a case of tumor-in-tumor metastasis abstract. Carcinoma metastasis to the thyroid is uncommon, but may be increasing. We describe here a patient with a metastasis of hepatocellular carcinoma (HCC) presenting within a medullary thyroid carcinoma (MTC). The thyroid tumor was detected synchronously with the hepatic lesion by FDG-PET imaging, and HCC metastasis within MTC was confirmed by histological analysis of the thyroid gland.

Positron-emission tomography for hepatocellular carcinoma: Current status and future prospects

“…In view of the potential value of PET-CT for extrahepatic lesions, PET-CT should be considered for initial HCC staging work-ups to formulate a plan for patients who are candidates for hepatic resection (HR) or LT[44]. Although CT, MRI, and bone scintigraphy are recommended for preoperative HCC staging, HCC metastasis to uncommon sites, such as the oral cavity, jaw, thyroid, and adrenal glands, may be detected only by 18 F-FDG PET-CT[43,46,47] and easily missed by conventional CT and MRI. Overall, 18 F-FDG PET-CT has additional value for HCC staging.…”

Invasion Patterns and Metastatic Patterns of Hepatocellular Carcinoma

“…In rare situations, and similar to other malignancies, HCC metastasizes into other neoplasms, e.g., medullary carcinoma of the thyroid (Sung et al 2011). Exceptionally, extrahepatic cancers metastasized to primary HCC, e.g., esophageal carcinoma (Doihara et al 1989), colorectal cancer (Maruyama et al 1990), and Hodgkin's lymphoma (Utsunomiya et al 2009).…”